Plastic tarps have several uses in the garden. As a wind-break and a shield from cold, snow, rain and hail plastic can help save tender crops from frost or damage from heavy rain or hail. Black plastic is especially useful in cooler climates to aid in warming the soil in the early part of spring. Here is picture of my corn plot in mid-May.
The weather this spring was quite warm for the early weeks of May. So, I decided to be bold and germinate the corn under the black plastic tarp. Normally, I don’t plant crops like corn or beans until late-May or early-June. After germination, I can pull off the tarp and the weather should continue to warm as we move toward the solstice. If we do get a night or two of cold I can place a clear plastic tarp over the plants at night. That should be sufficient to keep the young seedlings from becoming stunted.
Black plastic can also be used to suppress weeds. I have applied a single sheet of b.p. to cover the area where tomatoes and peppers will go. Let the plastic heat the soil for a few days then cut slits in sheet and place the plants in the soil. The plants may require a little extra watering, but they will have no competition from weeds.
Clear plastic is useful for making an expedient cold frame in the event of heavy rain, hail or frost.
Follow this link for complete instructions for making a greenhouse with PVC pipe and clear-poly plastic sheeting.
If this mild weather holds I expect to be picking peas at the end of October and into November.